This invention relates to no-bake and cold box acid curable foundry binders. Furan resins are recognized for their utility as acid curable foundry binders. In the no-bake version these resins are mixed with sand and then are cured or catalyzed with liquid acids. In the cold box version acid curable resins are mixed with sand and then are cured with acids which are gases.
The furan binders which are useful in the foundry arts as binders for sand may in general be described as binders which contain furfuryl alcohol. Included within this description are furfuryl alcohol resins, furfuryl alcohol/formaldehyde resins, urea/formaldehyde/furfuryl alcohol resins and phenol/formaldehyde furfuryl alcohol resins. It has been found that alkylated aromatic hydrocarbons will perform as solvents for furan binders. The use of the alkylated aromatic hydrocarbon as solvents for furan binders results in a cost reduction of the ultimate furan binder without a significant reduction in the physical properties of the foundry cores and molds made using the binder. Casting quality is unaffected by the use of the furan binder solutions made using alkylated aromatic solvents.